合肥市景观水环境综合评价

以合肥市的景观水体为研究对象,从景观水资源的自然属性和美学属性研究入手,探讨了城市水体的景观、环境和经济效应及美学特征,并在此基础上,应用"专家评估"与"系统调查分析"相结合的评价方法,对主要景观水体的美景度进行了综合评价。结果表明:合肥市内水景中美感度最高的是黑池坝风景区(113.3),其次是银河公园风景区(60.9),再次是雨花塘风景区(46.4),而美景度较差的是杏花公园(-27.5)和南淝河(-4.9)。     

塔里木河流域生态脆弱性评价研究

塔里木河流域受自然及人为因素的影响,局部地区生态退化问题突出,从景观生态学的干扰性质理论和恢复生态学的观点出发,选择水资源系统、土地资源系统及植被资源系统及其10个综合性敏感因子对流域生态的敏感性及恢复力进行分析,并确定敏感因子的定量指标,定性代码及其权重和阈值,通过算术对数插值对敏感因子实际值进行规范化处理,并构建生态胁迫度。结果表明,塔里木河三源流阿克苏河流域、叶尔羌河流域、和田河流域及于流区的上、中、下游区生态胁迫度分别为0．13、0．25、0．30、0．31、0．57及0．84,在评价分级标准的限定下,其对应的生态脆弱性程度依次为轻微脆弱、一般脆弱、一般脆弱、一般脆弱、中等脆弱及严重脆弱。     

工业固体废物容量总量控制的研究

针对工业固体废物如何进行容量总量控制的问题,在研究工业固体废物中有毒有害物质污染迁移转化规律的基础上,提出了相对工业固体废物中有毒有害物质进入大气、地表水体、地下水和在生物体内积累的相对容量总量控制概念,并探讨了城市或区域工业固体废物容量总量控制的确定方法     

Pahokee泥炭腐殖酸的相对分子量分布特征及其对菲的吸附影响

使用切面流超滤方法,将Pahokee泥炭中分离出的腐殖酸分为具有不同相对分子质量的8个级分(UF1:<1k;UF2:1～3k;UF3:3～5k;UF4:5～10k;UF5:10～30k;UF6:30～50k;UF7:50～100k:UF8:>300k),表明该泥炭中的腐殖酸主要分布于几个高相对分子量级分中(UF5,UF6和UF8),可占所提取的腐殖酸质量的83 5%.体积排阻色谱的流出曲线说明可以通过超滤手段将腐殖酸这种复杂的、非均匀性的大分子物质分成相对均一的、窄相对分子量分布的分子.而两种方法所测相对分子量的差异可能与两个操作系统间不同的操作条件有关.各超滤级分的腐殖酸对菲的吸附实验说明相对分子量是影响腐殖酸吸附的一个重要参数;随相对分子量的增加,腐殖酸对菲的吸附及其非线性特征均增强.     

Settle3D软件在半填半挖黄土路基变形分析中的应用*

为揭示半填半挖黄土路基的变形规律及其影响因素,为高填方黄土路基稳定性的评估提供科学依据。以国道G310典型半填半挖黄土路基为例,运用Settle3D软件对不同工况条件下的黄土路基进行精确建模与系统分析。结果表明:自然条件下路基左右侧沉降量差别不大,而降雨条件下原状黄土侧的沉降大于压实黄土侧的沉降,土层交界处沉降差异显著;降雨条件下中心点的沉降曲线在原填土交界处发生转折,表明压实效果显著;各施工阶段间沉降量差值呈非线性减小趋势,但降雨条件下的稳定时间更长。因此施工中控制路基压实度和采取合理的路基防水排水措施非常重要。     

宁夏土壤水文参数空间分布及干旱指标改进研究

土壤相对湿度是干旱监测和评估中最常用的指标之一,但这一指标的有效水下限较为模糊,实际应用中会将一部分土壤有效水排出在外,从而高估干旱的程度,因此有必要对其进行改进。利用2016-2019年宁夏回族自治区气象局122个土壤湿度观测站0-50 cm土壤田间持水量(%)和凋萎湿度(%)的测定数据,分析了宁夏境内土壤水文参数空间分布特征,并引入土壤相对凋萎湿度,以改善当前干旱监测评估中最旱等级土壤水下限模糊的问题。结果表明:宁夏0-20 cm和20-50 cm土壤水文参数的空间分布特征较为相似,田间持水量、凋萎湿度、有效水和相对凋萎湿度的波动范围均呈南低北高的特点;数值大小上,田间持水量、凋萎湿度、有效水整体呈南大北小,而相对凋萎湿度南小北大;分布区间上,田间持水量、凋萎湿度、有效水、相对凋萎湿度集中在15.0%-25.0%、3.0%-6.0%、10.0%-20.0%、10.0%-30.0%之间。基于相对凋萎湿度改进的干旱指标,在宁夏除特旱上限对应的土壤相对湿度波动范围较大外,轻旱、中旱和重旱对应的土壤相对湿度空间波动范围均较小;轻旱、中旱、重旱和特旱的上限对应的土壤相对湿度分别主要介于82.1%-90.0%、64.2%-80.0%、46.3%-60.0%、28.4%-50.0%之间。改进后的干旱指标其物理意义更加明确,能客观反映较低土壤水分对植物有效性真实情况,研究对提高干旱监测评估的准确性有一定现实意义。     

中国省际水-能源-粮食耦合协调度及影响因素研究

我国水资源、能源、粮食消费量均居世界首位,如何保证水资源-能源-粮食之间的协调发展成为我国实现可持续发展急需解决的关键问题。基于耦合协调度模型测算2003—2015年我国省际水-能源-粮食耦合协调度,并结合ESDA方法和空间计量模型探讨水-能源-粮食耦合协调度的空间相关性及影响因素。结果表明:①我国省际水-能源-粮食子系统及综合评价指数水平较低,呈现上升态势,其空间分布格局与我国水-能源-粮食资源禀赋分布格局相一致。②我国省际水-能源-粮食耦合度已处于高水平,但我国省际水-能源-粮食耦合协调度水平较低,呈现出稳定上升态势,存在较大的提升空间;我国省际水-能源-粮食耦合协调度具有显著的空间分异规律,各地区空间差异性明显,呈现出东北>中部>东部>西部的空间分布格局。③我国省际水-能源-粮食耦合协调度呈正向空间自相关性,集聚状态明显,但分布格局不够稳定,易发生变动。④我国省际水-能源-粮食耦合协调度的影响因素主要有经济发展水平、经济集聚、技术进步、教育、人口和农林支出。因此,国家应针对水、能源、粮食的协调发展进行顶层设计,统筹考虑水、能源、粮食与产业布局及行业外部影响的关系。通过技术进步来提升水、能源、粮食的利用效率,保证协调发展的质量。各省市则应结合自身实际情况,制定有针对性的措施,弥补短板,促进其水-能源-粮食的协调发展。     

Evaluation on the development degree of China’s seven pilot carbon markets

China is preparing to establish a nationwide carbon market in 2017, and in order to facilitate this goal, seven pilot carbon markets have been under study for the past few years. This paper summarizes the operation experience and challenges of the seven pilot carbon markets in China. It has been widely accepted that the essence of a carbon market is to solve environmental problems through market mechanisms, with environmental benefit being the fundamental purpose, market mechanism being the key measure, and policies and regulations being an important guarantee for an orderly carbon market. Therefore, this paper constructs an evaluation index system composed of 34 detailed sub-indexes in three dimensions, such as environmental constraint force, market resource allocation ability, and supporting policies and facility completeness. Through analyzing the operation data from 2013 to 2016, the weights of the sub-indexes are obtained. In addition, the study obtains experts’ opinions from over 10 carbon permits exchanges, consultancy firms and research institutions in China, and conducts a comprehensive evaluation on the development degree of the seven pilot carbon markets. Results show that the pilot carbon markets that include private SMEs as the covered entities for emissions control present relatively higher environmental constraint force. But too many covered entities could increase the difficulty of market performance management, while the pilots that include high energy-consuming state-owned enterprises as the entities for emissions control demonstrate a phenomenon of “high market compliance rate with low trading volume”. The resource allocation capability of China’s carbon market has not been effectively brought into play, and low degree of market participation has become an important constraint factor for market development. Due to the lack of laws and regulations at the national macro-level, the legally binding force of the pilot markets construction is obviously insufficient, and the supporting policies are lacking foresights. Generally, the development of China’s pilot carbon markets is still in such a fragmented state as in the aspects of environment, market and policy development, and the market operation has not yet achieved the purpose of solving environmental problems through market mechanisms. Accordingly, policy recommendations pointed out by this study are that tightening the allowance of free quota and progressively increasing the auction proportion, improving legal construction, increasing the services and products of carbon finance and standardizing the order of market transactions, enhancing capacity building of local governments and promoting the participation willingness and capability of emissions control entities, will be necessary.     

Factors affecting the quantitative uncertainty of the estimated short-term intake. Part II—Practical examples

ABSTRACT

The effects of the spread of residue concentrations in the samples derived from the selected supervised trials and the number of trials were studied on the magnitude and uncertainty of the short-term dietary intakes calculated with the proposed new procedure (IESTI_p) and that one used currently by the FAO (Food and Agriculture Organization) and WHO (World Health Organization) Joint meeting on Pesticide Residues (JMPR) (IESTI_c). The residue data of 10 pesticides were obtained from supervised trials conducted on apples and pears. The methods described in Part I were used for the calculations of the uncertainty. The results indicate that the ratio of IESTI_P to IESTI_c (φ_IESTI) is directly proportional to the ratio of the estimated maximum residue level (MRL), recommended by the JMPR; to the highest residue (HR) observed in supervised trials, and it may have a wide range depending on the particular conditions. The φ_IESTI becomes greater with the increase of the difference between the mrl or maximum residue limit (MRL, established by the Codex Alimentarius Commission, CAC) and HR, and becomes smaller if the difference between the large portion (LP) and unit mass (U) decreases. The φ_IESTI ranged between 2 and 5.1 in the 16 cases examined indicating that the IESTI_p calculation method leads to higher intake estimates. The ratio of CV_IESTIp and CV_IESTIc ranged typically between 0.62 and 1.71. It rapidly increased up to 12 trials. For a larger number of trials, the ratio remained practically constant (1.69–1.71). The processing factor (PF) equally affects the MRL and HR values, therefore, it will not practically influence the φ_IESTI. The uncertainty of the estimated median residues depends on the spread and number of values in the residue datasets, which affects the uncertainty of the conversion factor (CF) and subsequently the uncertainty of the estimated IESTI_p. Residue values obtained from minimum nine independent trials are required for the correct calculation of the 95% confidence intervals of the calculated median residues. The uncertainty of the analytical results directly affects the median, HR values and indirectly the calculated mrl and the MRL derived from it. Therefore, it should also be considered for the calculation of the combined uncertainty of the conversion factors. For the correct interpretation of the results of dietary exposure calculations, the upper 95% confidence limit of the short-term intake should also be considered. However, it is not the current practice of regulatory agencies or JMPR.     

基于农户视角的秸秆机械化 还田服务绩效评价及其障碍因子诊断——来自冀、鲁、皖、鄂四省的调查

农户是秸秆机械化还田服务的直接受益者,从农户视角来评价秸秆还田服务绩效水平,并诊断其可能的障碍因子,可为提高秸秆还田服务绩效提供决策依据。从秸秆还田服务过程和秸秆还田服务结果两个阶段、农户经济人属性和社会人属性两个方面构建秸秆机械化还田服务绩效评价指标体系,采用基于熵权改进的TOPSIS法和障碍度模型,通过对冀、鲁、皖、鄂四省农户的问卷调查,评价秸秆机械化还田服务绩效水平及障碍因子。结果显示：山东省秸秆机械化还田服务绩效水平为“优秀”,河北省的绩效水平“一般”,湖北省和安徽省绩效水平“较差”。秸秆机械化还田服务绩效水平最重要的影响因素是农户对秸秆机械化还田结果的评价,其次是还田过程阶段的评价;影响秸秆机械化还田服务绩效水平的主要因子为还田服务后社会发展情况、耕地病虫害情况、还田政策补贴及还田后耕地熵情的评价。为此,提高秸秆机械化还田服务的绩效水平,加强对秸秆机械化还田服务的宣传推广,积极完善秸秆机械化还田补贴等政策措施,提高还田后配套化设施及服务供给,应是当前政策关注的重心。